Vol. 60.] LATER FORMATIONS SURROUNDING THE DARDANELLES. 255 



trachyte, dacite, trachyandesite, hornblende- and 

 augite-andesite, labradorite, and basalt (6, pp. 184-85). 



In Tenedos, Spratt describes the north-eastern point of the island 

 as ' trachyte ' (1, p. 214). I found that there is also an exposure of 

 volcanic rock along more than half of the eastern coast, extending 

 farther south than Tar Point. 



In the valleys of the Scainander (Men Dere) and of the Thym- 

 brius(Kemer Dere), Mr. Calvert found basalts between Bali Dagh 

 and Akchc Keui, in the form of coulees flowing from the crystalline 

 marble and serpentine-hills, and covering and indurating the debris 

 at their feet. At the White Cliffs, below Chanak in the Dardanelles, 

 he also found the red clays and calcareous beds much disturbed 

 and altered by an outburst of volcanic rock. 1 A specimen of this 

 rock has been identified as an unusual variety of biotite-andesite 

 (see Appendix I, p. 276). 



The Tertiary volcanic rocks show a marked tendency to appear 

 along the coasts of the Eocene Sea, and in long belts following the 

 strikes of the foldings of the Lower Tertiary strata. 



The widespread late Eocene and Oligocene volcanic rocks would 

 certainly seem to imply considerable differences in the relief of the 

 land, at the time at which they were ejected ; and it is difficult to 

 reconcile this with the equally widespread coal-seams, presumably 

 requiring shallow lakes or marshy country with only slight 

 differences of level. 



VJ. Miocene. 



I propose to demonstrate the existence of Helve tian- 

 Tortonian deposits, probably vestiges of a Lower 

 Miocene sea-connection between the Ponto-Caspian 

 and the Mediterranean. These are overlain by fresh- 

 water Sarmatic strata with lignites and naphtha, suc- 

 ceeded by marine (Mactra-) limestones, which occupy 

 nearlv the whole of the northern shore of the Sea of Marmora, to 

 the exclusion of the Levantine Beds, suggested by F. von Hochstetter 

 (2, map) as filling up this area. These J/artra-limestones are in 

 direct continuation of those already known in the Southern Troad 

 and in the Dardanelles. There is also evidence of the occurrence 

 of Sarmatic strata in Imbros and in Tenedos. 



At Eregli, on the northern shore of the Gulf of Xeros, and thence 

 several miles inland to Fakirma, occurs an exposure of sands and 

 sandy limestones, with a slight southerly dip. These beds, close to 

 the present sea-level at Eregli, contain typical Helvetian-Tortonian 

 fossils — Pecten aduncus. Alectryonia Virleti, and Anadara diluvii, 

 also Ostrea lamellosa, of which specimens are now in the British 

 Museum (Natural History) : see Appendix II, p. 285. Prof. Suess 

 says that, from a large number of measurements, he has arrived 

 at the conclusion that the shore-line at this epoch was 440 to 

 450 metres above the existing level of the sea (15, pp. 412-13) ; 

 and the Eregli beds probably owe their preservation to the fact of 



1 Communication to the Author. 



